Cytotoxic Effects of Cadmium and Paraquat on Avian Skin Fibroblasts

Recent studies have shown that wild birds may act as potential barometers of environmental pollution. We studied the effects of two environmental toxicants, cadmium (Cd) and paraquat (PQ), on the skin fibroblasts of three wild birds including, green-winged teal (Anas carolinensis), bobwhite quail (Colinus virginianus), and house sparrow (Passer domesticus) of the orders Anseriformes, Galliformes and Passeriformes, respectively. The toxicities were represented as 50% lethal concentrations (LC50), a dose causing death of 50% of the cells after 24 h exposure of toxicant. The LC50 of Cd for the skin fibroblasts from green-winged teal, bobwhite quail, and house sparrow were found to be 0.015 mM, 0.078 mM, and 0.176 mM. The LC50s of PQ for the same cells were 4.58 mM, 25.32 mM, and 36.53 mM, respectively. These results indicated that cells from water fowl may be highly susceptible to Cd and PQ poisoning whereas house sparrow was the least susceptible. Further studies are warranted to investigate the mechanism of differential susceptibility of birds to environmental toxins.